Arakawa Lock Gate, Navigation lock in Komatsugawa and Higashisuna, Japan

Arakawa Lock Gate is a navigation lock in Komatsugawa and Higashisuna that regulates water levels between different sections of the river in eastern Tokyo. The structure allows boats to pass safely through the waterway system while maintaining controlled water flow.

The lock opened in 2005 and replaced older water management systems in an area with a long history of river shipping. The Arakawa waterway system had previously played an important role in transporting goods through the city.

The lock gate shows how Tokyo connected traditional river shipping with modern water management systems. The area around it preserves the memory of times when goods like rice and soy sauce traveled by water.

The lock operates daily except December 31 to January 3, the first Sunday of each month, and the first three Sundays of September. Hours are 8:45 to 16:30, extended to 18:00 from June 1 to August 31. Passage is free and takes about 20 minutes; boats up to 55 m long, 14 m wide and 4.5 m high can use it, but personal watercraft cannot.

The lock was designed to withstand an earthquake on the scale of the 1995 Great Hanshin-Awaji earthquake, so it can serve as a relief supply route during a disaster. On 22 May 2023 the Emperor visited the gate.